Herpes viruses inflict a wide range of diseases against humans and animals. For instance, herpes simplex viruses, types 1 and 2 (HSV-1 and HSV-2), are responsible for cold sores and genital lesions, respectively; varicella zoster virus (VZV) causes chicken pox and shingles; and the human cytomegalovirus (HCMV) is a leading cause of opportunistic infections in immunosuppressed individuals.
Over the past two decades, a class of compounds known as the purine and pyrimidine nucleoside analogs has received the most attention by investigators in the search for new therapeutic agents for treatment of herpes virus infections. As a result, several nucleoside analogs have been developed as antiviral agents. The most successful to date is acyclovir which is the agent of choice for treating genital HSV infections. Another nucleoside analog, ganciclovir, has been used with some success in treating HCMV infections.
Nevertheless, in spite of some significant advances, the need for effective, safe therapeutic agents for treating herpes viral infections continues to exist. For a review of current therapeutic agents in this area, see R. E. Boeheme et al., Annual Reports in Medicinal Chemistry, 1995, 30, 139.
Azetidin-2-one derivatives have been reported in the literature as having a variety of biological activities; mainly antibacterial, antiinflammatory, antidegenerative, etc. However, azetidin-2-one derivatives have not been reported to be antiviral agents against herpes viruses.
The following references disclose azetidin-2-ones having biological activity:
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